App::PropertyDirection vs. App::PropertyVector?

[Jolbas]

How do I drill down to Axis or RawAxis?

They are part of either a App::PropertyPlacement or App::PropertyRotation. They are vectors but aren't standalone properties and neither App::PropertyDirection nor App::PropertyVector

Axis is the RawAxis normalized upon call
RawAxis is the one you see and set in the property view after expanding the Placement property, but there it's called just Axis

In Python the obj.Placement.Rotation.RawAxis is readonly. but obj.Placement.Rotation.Axis = App.Vector(1,2,3) sets the RawAxis and then obj.Placement.Rotation.Axis will return it as normalized: Vector (0.2672612419124244, 0.5345224838248488, 0.8017837257372732)

[edwilliams16]

OK. So neither are App::PropertyDirection Will have to look elsewhere for its use.

[onekk]

OK. So neither are App::PropertyDirection Will have to look elsewhere for its use.

Where did you find it?

I was curious and I've tried to search sources using github search bar.

But I have not managed to find anything.

Regards

Carlo D.

[Jolbas]

I would say, the App::PropertyDistance App::PropertyDirection, App::PropertyPosition and App::PropertyVectorDistance are all equal. They all have length units on their coordinates, for example meters. App::PropertyVector is the base for those and have no unit. That means that units are discarded for expressions on PropertyVector and a default unit is added on the other property types.

Edit: Corrected App::PropertyDistance to App::PropertyDirection

[edwilliams16]

That means that units are discarded for expressions on PropertyVector and a default unit is added on the other property types.

So a PropertyDirection has units? Seems counter-intuitive. If I decomposed a vector

Code: Select all

vector = direction_unit_vector * length

I would have expected length to carry the units.

[Jolbas]

So a PropertyDirection has units? Seems counter-intuitive.

I agree. It seems unnecessary to have a unit on the direction. I do not fully understand the handling of units here. The PropertyDirection is presented with units in property view.

This expression on a PropertyDirection works:

Code: Select all

anotherDirectionProperty * 5mm

But this expression on the x coordinate of a PropertyDirection does not work:

Code: Select all

anotherDirectionProperty.x * 5mm

The last expression works on a PropertyVector.x which just discards any unit.

[Roy_043]

Where did you find it?

https://freecad.github.io/SourceDoc/dd/ ... ceApp.html
FeaturePython_Custom_Properties

[Roy_043]

The PropertyDirection is presented with units in property view.

Thanks, I missed that.

This works

Code: Select all

obj = FreeCAD.ActiveDocument.addObject("App::FeaturePython", "InternalObjectName")
obj.Label = "User-friendly label"
obj.addProperty("App::PropertyDirection", "ThePropertyName", "Subsection", "Description for tooltip")
obj.ThePropertyName = (1.0, 2.0, 3.0)

len = FreeCAD.Units.Quantity(123, App.Units.Length)
print(obj.ThePropertyName * len)
print(obj.ThePropertyName.z * len)